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91.
Massimo Mecella Barbara Pernici 《The VLDB Journal The International Journal on Very Large Data Bases》2001,10(1):2-15
Component-based approaches are becoming more and more popular to support Internet-based application development. Different
component modeling approaches, however, can be adopted, obtaining different abstraction levels (either conceptual or operational).
In this paper we present a component-based architecture for the design of e-applications, and discuss the concept of wrapper
components as building blocks for the development of e-services, where these services are based on legacy systems. We discuss
their characteristics and their applicability in Internet-based application development.
Received: 30 October 2000 / Accepted: 9 January 2001 Published online: 28 June 2001 相似文献
92.
Barbara Gengler 《Network Security》2001,2001(3):6
An industry consortium focused on ensuring that all PCs are secure for electronic business transactions has announced the release of its first version specification. The Trusted Computing Platform Alliance (TCPA), backed by founding members Compaq, Microsoft, Hewlett-Packard, IBM and Intel, said that the specification will adopt the combination of a hardware and a software approach, which includes a security chip that encrypts data whether filed locally, or sent over the Internet by E-mail. 相似文献
93.
Matthew Arnold Michael Hsiao Ulrich Kremer Barbara G. Ryder 《International journal of parallel programming》2001,29(2):111-137
The frequent occurrence of implicitly thrown exceptions poses one of the challenges present in a Java compiler. Not only do these implicitly thrown exceptions directly affect the performance by requiring explicit checks, they also indirectly impact the performance by restricting code movement in order to satisfy the precise exception model in Java. In particular, instruction scheduling is one transformation that is restricted by implicitly thrown exceptions due to the heavy reliance on reordering instructions to exploit maximum hardware performance. The goal of this study is two-fold: first, investigate the degree to which implicitly thrown exceptions in Java hinder instruction scheduling, and second, find new techniques for allowing more efficient execution of Java programs containing implicitly thrown exceptions. Experimental results show that with aggressive scheduling techniques, such as superblock scheduling, the negative performance impact can be greatly reduced. 相似文献
94.
Two samples of naturally occurring pyrite were treated with acetyl acetone, silanes, humic acids, lignin-NaOH mixture, and oxalic acid. The corrosion rate of pyrite was observed to decrease significantly due to the surface treatment by the chemicals used in this study. Surface characterization methods indicate that phenyl triacetoxy silane forms a passive coating a few Angstroms thick on the pyrite, thus preventing its dissolution in 1M H2SO4. 相似文献
95.
Janwillem Liebrand Margreet Z. Zwarteveen Philippus Wester Barbara van Koppen 《国际水》2013,38(7):773-787
Through investigating the reactions of commercial farmers to land and water reforms in the Trichardtsdal-Ofcolaco area, Limpopo Province, Olifants Basin, South Africa, from 1997 to 2006, it is shown that water claims are key to land redistribution processes, and that commercial farmers make strategic use of arguments for nature conservation and ecological stewardship to defend their claims to water. Given these observations, caution is warranted with respect to the implementation of land and water reforms as separate policy packages; it may be more effective to design water and conservation policies as an integral part of land reform programmes. 相似文献
96.
This study examined the question, ‘What is the impact of a digital math intervention on secondary ELL students’ mathematical capabilities and perceptions of their future possibilities?’ The hypothesis was that through its direct effect on increasing students’ math ability and its indirect effect on increasing students’ perceived math self-efficacy, the digital intervention affects students’ perceptions of their functionings and future possibilities. A path analysis, with qualitative data nested into the design, was used to analyze the conceptualized relationships. The study was conducted with 50 ninth-and-10th-grade Hispanic students in a Colorado high school, over 6 months. The primary finding was that through its direct effect on increasing students’ math ability and its indirect effect on increasing students’ perceived math self-efficacy, the digital intervention improved students’ perceptions of their functionings and future possibilities. What this study specifically underscores is the importance of taking a coherent and purposeful approach toward the design of digital student-directed educational technology, especially for ELL students who may have specific learning needs. 相似文献
97.
Glenn Melissa J.; Lehmann Hugo; Mumby Dave G.; Woodside Barbara 《Canadian Metallurgical Quarterly》2005,119(3):806
The authors explored the possibility that there are different neural consequences, beyond the primary site of brain damage, following perirhinal cortex (PRh) lesions made in different ways. Fos expression was used as a marker for neuronal activation and compared across the forebrains of rats that underwent the different types of surgery. Electrolytic and excitotoxic PRh lesions produced dramatic increases in Fos expression in the cortex, and excitotoxic and aspiration PRh lesions increased Fos expression in the dentate gyrus. These data are consistent with the hypothesis that different lesion methods have separable effects on neural function in regions outside the lesion site that could account for inconsistencies in the literature regarding the behavioral effects of PRh lesions on tests of spatial memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Hindson Barbara; Byrne Brian; Fielding-Barnsley Ruth; Newman Cara; Hine Donald W.; Shankweiler Donald 《Canadian Metallurgical Quarterly》2005,97(4):687
Preschool children at familial risk for reading disability were assessed on cognitive and linguistic variables and compared with preschoolers without familial risk. Risk children displayed performance profiles resembling those of older children with reading disability. Each group received intensive instruction in phonemic awareness and structured book reading. Instructed risk children made somewhat smaller gains than the nonrisk and required more teaching sessions to reach criterion. Rhyme and phoneme awareness predicted instruction outcome levels, and vocabulary and verbal short-term memory predicted number of teaching sessions to criterion. In kindergarten, the nonrisk group outperformed the risk group on reading and spelling, although the risk group reached grade-appropriate levels. At-risk children can be helped by appropriate preschool instruction, but they require more sustained teaching than nonrisk preschoolers. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Golden-Kreutz Deanna M.; Thornton Lisa M.; Wells-Di Gregorio Sharla; Frierson Georita M.; Jim Heather S.; Carpenter Kristen M.; Shelby Rebecca A.; Andersen Barbara L. 《Canadian Metallurgical Quarterly》2005,24(3):288
The authors investigated the relationship between stress at initial cancer diagnosis and treatment and subsequent quality of life (QoL). Women (n = 112) randomized to the assessment-only arm of a clinical trial were initially assessed after breast cancer diagnosis and surgery and then reassessed at 4 months (during adjuvant treatment) and 12 months (postadjuvant treatment). There were 3 types of stress measured: number of stressful life events (K. A. Matthews et al., 1997), cancer-related traumatic stress symptoms (M. J. Horowitz, N. Wilner, & W. Alvarez, 1979), and perceived global stress (S. Cohen, T. Kamarck, & R. Mermelstein, 1983). Using hierarchical multiple regressions, the authors found that stress predicted both psychological and physical QoL (J. E. Ware, K. K. Snow, & M. Kosinski, 2000) at the follow-ups (all ps 相似文献
100.
Michael L. Bernard Barbara S. Chaparro Melissa M. Mills Charles G. Halcomb 《International journal of human-computer studies》2003,59(6):823-835
Times New Roman and Arial typefaces in 10- and 12-point, dot-matrix and anti-aliased format conditions were compared for readability (accuracy, reading speed, and accuracy/reading speed), as well as perceptions of typeface legibility, sharpness, ease of reading, and general preference. In assessing readability, the 10-point anti-aliased Arial typeface was read slower than the other type conditions. Examining perceptions of typeface legibility, sharpness, and ease of reading detected significant effects for typeface, size, and format. Overall, the 12-point dot-matrix Arial typeface was preferred to the other typefaces. Recommendations for appropriate typeface combinations for computer-displayed text are discussed. 相似文献